The present invention relates to a riveting method and a building panel obtained by the riveting method.
A rivet is a clamping member having a head and a shank. Clamping by a usual rivet is performed by a method of forming a rivet hole to stacked metal plates by means of drilling or the like, inserting a rivet into the hole to protrude a shank, and applying a force (caulking) to the protruded shank to form a head at the end of the shank. Such rivet clamping has a merit, for example, of not requiring heating at high temperature for metal plates to be clamped.
However, since rivet heads are present on both surfaces of the clamped metal plates, the rivet can not always be said to be an appropriate clamping means when the surface of one of the metal plates is utilized as a decorative surface. Further, if one of the metal plates is thin, for example, having a thickness of not more than 1 mm, surface distortion is caused upon fabrication of the rivet hole or caulking operation, which is particularly disadvantageous, for example, in a case of conducting smooth coating on the decorative surface.
In view of the foregoing situations, as a result of the present inventors' various studies on the structure of a rivet, it have been found that upon clamping a metal sheet having a thickness of not more than 1 mm and a metal plate having a thickness of more than the thickness of the metal sheet, by using a specified rivet, and adhesion-bonding a synthetic resin sheet to the surface of the metal sheet having a thickness of not more than 1 mm, and adhesion-bonding a metal sheet having a thickness of not more than 1 mm on the surface of the synthetic resin sheet to function the synthetic resin sheet as a cushioning material, surface distortion of the metal sheet is prevented, the rivet end can be buried to the inside of the synthetic resin sheet, and the drawing strength of the rivet is improved remarkably by the metal sheet in contact with the other metal plate to be clamped although the sheet is thin. On the basis of the finding, the present invention has been attained.